fn main() {
    let sys = actix::System::new("test");

    // load ssl keys
    let mut builder = SslAcceptor::mozilla_intermediate(SslMethod::tls()).unwrap();
    builder.set_private_key_file("./examples/key.pem", SslFiletype::PEM).unwrap();
    builder.set_certificate_chain_file("./examples/cert.pem").unwrap();
    let acceptor = builder.build();

    let num = Arc::new(AtomicUsize::new(0));

    // bind socket address and start workers. By default server uses number of
    // available logical cpu as threads count. actix net start separate
    // instances of service pipeline in each worker.
    Server::default()
        .bind(
            // configure service pipeline
            "basic", "0.0.0.0:8443",
            move || {
                let num = num.clone();
                let acceptor = acceptor.clone();

                // service for converting incoming TcpStream to a SslStream<TcpStream>
                (move |stream| {
                SslAcceptorExt::accept_async(&acceptor, stream)
                    .map_err(|e| println!("Openssl error: {}", e))
            })
            // convert closure to a `NewService`
            .into_new_service()

            // .and_then() combinator uses other service to convert incoming `Request` to a `Response`
            // and then uses that response as an input for next service.
            // in this case, on success we use `logger` service
            .and_then(logger)

            // Next service counts number of connections
            .and_then(move |req| {
                let num = num.fetch_add(1, Ordering::Relaxed);
                println!("processed {:?} connections", num);
                future::ok(())
            })
        }).unwrap()
        .start();

    sys.run();
}